#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <stdlib.h>
#include <assert.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>

int main(int argc, char const *argv[])
{
	if (argc <= 2)
	{
		printf("usage: %s ip_address port_number\n", basename(argv[0]));
		return 1;
	}
	const char* ip = argv[1];
	int port = atoi(argv[2]);

	struct sockaddr_in address;
	bzero(&address, sizeof(address));
	address.sin_family = AF_INET;
	inet_pton(AF_INET, ip, &address.sin_addr);
	address.sin_port = htons(port);
	int sock = socket(PF_INET, SOCK_STREAM, 0);
	assert(sock > 0);
	int ret = bind(sock, (struct sockaddr*)&address, sizeof(address));
	assert(ret != -1);
	ret = listen(sock, 5);
	assert(ret != -1);
	sleep(20);
	struct sockaddr_in client;
	socklen_t client_addrlength = sizeof(client );
	int connfd = accept(sock, (struct sockaddr*)&client, &client_addrlength);
	if (connfd < 0)
	{
		printf("errno is: %d\n", errno);
	}
	else
	{
		char remote[INET_ADDRSTRLEN];
		printf("connected with ip: %s and port: %d\n", 
			inet_ntop(AF_INET,&client.sin_addr,remote,INET_ADDRSTRLEN),
			ntohs(client.sin_port));
		close(connfd);
	}

	close(sock);
	return 0;
}
